Hmmm, and I thought you needed an oil filter. Look at the TMs Chainbreaker pointed out in post #14. You are looking for the NSN of a 'filter', 'fuel filter', 'air filter'.... Search those terms when you get the TM with lots of NSN numbers. Some of the TMs are specific to the Engine, the Operator, other components. Investigate them all.
I will elaborate. Some, but not ALL gen sets have TM's that cover JUST the gen set, and another set of TM's that cover JUST the engine. So its important to have ALL the TM's. You don't really have to use the search function in a parts TM. Just open the TM in your PDF program, click on TOC and then run down the list, (the oil, fuel and air filter all just happen to be on the first page of the engine book you want.) till you find the oil filter and click on the red box. It will bring you the the information page. Scroll upwards and you can see the picture. Its that simple. The real secrite here, is you need to crack the books.
I got a 'Filter, Fluid Pressure' with an NSN of 4330-00-025-3493. Bad NSN. Search Parttarget under the part number 'MS51085' and you'll get a new NSN of 2910-00-025-3493. Parttarget lists a bunch of manufacturers and part numbers. Purolator Facet is one:
https://www.ebay.com/itm/PUROLATOR-...RT-NUMBER-1742570-FREE-SHIPPING-/202079077936
I got a 'Strainer, Sediment' with an NSN of 2910-00-905-9792. Parttarget gives me a bunch of manufacturers and part numbers. Like this:
https://www.amazon.com/Filter-Sediment-Briggs-Stratton-295984/dp/B07P96YK9V
Air filter is in there, too. TMs are very helpful when combined with sites like Parttarget.